ZURICH (Reuters) - Roche is pressing ahead with two skin cancer trials that combine its immunotherapy Tecentriq with other drugs after early data showed the treatments were well-tolerated and effective in a small number of patients, the company said Monday.

One study combined Tecentriq with Cotellic and Zelboraf in 30 patients with untreated BRAFV600 mutation-positive metastatic melanoma, the other Tecentriq with Cotellic for 10 patients with BRAF-wild-type and BRAF-mutant metastatic melanoma.

Both now move into phase III late-stage pivotal trials.

After winning approval for Tecentriq earlier this year, first for bladder cancer and more recently for lung cancer, Roche is now trying it with other drugs in hopes that new combinations will result in potent weapons against cancer.

Of Roche's 50 immunotherapy trials underway, 40 are with different combinations of medicines.

"We are encouraged by these early results which demonstrate a high proportion of people responded to these investigational combination therapies," said Sandra Horning, Roche's chief medical officer, in a statement.

Though the Roche studies are just getting off the ground, analysts said the news so far looks good.

"Even when the data they are presenting was taken from a sample of only a few patients, the efficacy without the use of any chemotherapy is certainly extraordinarily high," Zuercher Kantonalbank analyst Michael Nawrath wrote in a note to investors.

Other companies, including Bristol-Myers Squibb, are also pursuing immunotherapy combinations.

Roche shares rose 1.6 percent in early trading on Monday. They have lost almost 20 percent of their value this year, compared with the Stoxx Europe 600 Health Care index's 16.4 percent drop.